.box{border:1px solid #ccc; border-radius:5px; margin: 100px; position:absolute;top:-35px;left:330px;z-index:1;background-color: #fff;}
        .a1,.a2{width:0; height:0; overflow:hidden; border-width:10px; border-style:dotted dotted solid; position:absolute}
        .abox{position: absolute; width:20px; height: 20px; left:80px; top:-20px}
        .a1{border-color: transparent transparent #ccc;  top:-1px}
        .a2{border-color: transparent transparent #FFFFFF;  top:0px}